Significance of plasma N-terminal pro-brain natriuretic peptide in patients with systemic sclerosis-related pulmonary arterial hypertension

Phenotypes of patients with systemic sclerosis in the Chinese Han population: a cluster analysis

OBJECTIVE

Systemic sclerosis (SSc) is a heterogeneous connective tissue disease that is commonly subdivided into limited cutaneous SSc (lcSSc) and diffuse cutaneous SSc (dcSSc) based on the extent of skin involvement. This subclassification may not reflect the full range of clinical phenotypic variation. This study aimed to investigate clinical features and aggregation of patients with SSc in Chinese based on SSc manifestations and organ involvements, in order to achieve precise treatment of SSc early prevention of complications.

METHODS

In total 287 SSc patients were included in this study. A cluster analysis was applied according to 13 clinical and serologic variables to determine subgroups of patients. Survival rates between obtained clusters and risk factors affecting prognosis were also compared.

RESULT

In this study, six clusters were observed: cluster 1 (n = 66) represented the skin type, with all patients showing skin thickening. In cluster 2 (n = 56), most patients had vascular and articular involvement. Cluster 3 (n = 14) individuals mostly had cardiac and pulmonary involvement. In cluster 4 (n = 52), the gastrointestinal type, 50 patients presented with stomach symptoms and 28 patients presented with esophageal symptoms. In cluster 5 (n = 50), patients barely had any major organ involvement. Cluster 6 (n = 49) included 46% of all patients presenting with renal crisis.

CONCLUSION

The results of our cluster analysis study implied that limiting SSc patient subgroups to those based only on skin involvement might not capture the full heterogeneity of the disease. Organ damage and antibody profiles should be considered when identifying homogeneous patient groups with a specific prognosis. Key Points • Provides a new method of categorizing SSc patients. • Can better explain disease progression and guide subsequent treatment.

Current Trends in Vascular Biomarkers for Systemic Sclerosis: A Narrative Review

Systemic sclerosis (SSc, scleroderma) is a multifaceted rare connective tissue disease whose pathogenesis is dominated by immune dysregulation, small vessel vasculopathy, impaired angiogenesis, and both cutaneous and visceral fibrosis. Microvascular impairment represents the initial event of the disease, preceding fibrosis by months or years and accounting for the main disabling and/or life-threatening clinical manifestations, including telangiectasias, pitting scars, periungual microvascular abnormalities (e.g., giant capillaries, hemorrhages, avascular areas, ramified/bushy capillaries) clinically detectable by nailfold videocapillaroscopy, ischemic digital ulcers, pulmonary arterial hypertension, and scleroderma renal crisis. Despite a variety of available treatment options, treatment of SSc-related vascular disease remains problematic, even considering SSc etherogenity and the quite narrow therapeutic window. In this context, plenty of studies have highlighted the great usefulness in clinical practice of vascular biomarkers allowing clinicians to assess the evolution of the pathological process affecting the vessels, as well as to predict the prognosis and the response to therapy. The current narrative review provides an up-to-date overview of the main candidate vascular biomarkers that have been proposed for SSc, focusing on their main reported associations with characteristic clinical vascular features of the disease.

Diagnostic value of cardiac natriuretic peptide on pulmonary hypertension in systemic sclerosis: A systematic review and meta-analysis

OBJECTIVE

Pulmonary arterial hypertension (PAH) is a major cause of morbidity and mortality in systemic sclerosis (SSc). Many risk factors and predictors of outcomes have been identified in these patients. B-type natriuretic peptide (BNP) and N-terminal pro-BNP (NT-proBNP) serum levels are often elevated in SSc patients with early PAH. We conducted this systematic review and meta-analysis to estimate the diagnostic value of BNP/NT-proBNP in systemic sclerosis secondary pulmonary arterial hypertension (SSc-PAH).

METHODS

A systematic search was performed through PubMed, Embase, and Cochrane Library databases up to January 30, 2021. Stata 16.0 (Stata Corp, College Station, TX) was used to conduct the meta-analysis.

RESULTS

A total of 9 studies involving 220 SSc-PAH patients and 259 non-SSc-PAH controls were included. The values of sensitivity and specificity using BNP and NT-ProBNP as diagnostic tools were pooled in the diagnostic meta-analysis. The overall performance of BNP/NT-ProBNP detection was: pooled sensitivity, 0.67 (95% CI: 0.52 to 0.79); pooled specificity, 0.84 (95% CI: 0.75 to 0.91); pooled positive likelihood ratio, 4.3 (95% CI: 3 to 6.1); and pooled negative likelihood ratio, 0.39 (95% CI: 0.28 to 0.55). The subgroup analysis showed similar results. Funnel plots indicate that there is no evidence for publication bias.

CONCLUSIONS

Our results revealed that NT-proBNP has certain diagnostic value for PAH due to its better specificity and moderate sensitivity, but its clinical application value remains suboptimal and can not be a stand-alone decision-making diagnostic tool of SSc-PAH.

Screening for pulmonary arterial hypertension in systemic sclerosis: A systematic literature review

Pulmonary arterial hypertension (PAH) carries a high morbidity and mortality burden in Systemic Sclerosis (SSc). Therefore, PAH screening and early detection are pivotal. A systematic literature review (SLR) to search for all screening tools and modalities for SSc-PAH was performed in reference to right heart catheterization as diagnostic gold standard. Papers from 2 previously published SLRs and derived from a systematic search on Pubmed, EMBASE, Web of Science for papers published from 03/10/2017 to 31/12/2018 were manually included. A total of 199 papers were reviewed and 32 were extracted, with a low bias risk according to QUADAS2. Echocardiography, pulmonary function tests, clinical features and serum biomarkers were the most frequently tools used for screening, with different parameters combined in a variable fashion, as single item or as part of composite algorithms. Among the composite algorithms, the DETECT score, ESC/ERS 2009 or 2015 guidelines, ASIG and ITINER-air algorithms were the most commonly used in a wide range of patients. In different cohorts, DETECT and ASIG showed higher sensitivity and negative predictive value than ESC/ERS 2009. In conclusion, the literature shows echocardiography as the leading screening tool for SSc-PAH. In particular, systolic pulmonary arterial pressure (sPAP) and tricuspid regurgitation velocity (TRV), both as single items or part of composite algorithms, including also serum biomarkers, clinical and functional items, are the most frequent parameters evaluated.

Screening for pulmonary arterial hypertension in systemic sclerosis

Pulmonary arterial hypertension (PAH) is a dreaded complication of systemic sclerosis (SSc) that occurs in ∼10% of patients. Most individuals present with severe symptoms, significant functional impairment and severe haemodynamics at diagnosis, and survival after PAH diagnosis is poor. Therefore, early diagnosis through systematic screening of asymptomatic patients has the potential to identify PAH at an early stage. Current evidence suggests that early diagnosis and treatment of PAH in patients with SSc may lead to better clinical outcomes. Annual screening may include echocardiography, but this can miss some patients due to suboptimal visualisation or insufficient tricuspid regurgitation. Other options for screening include the DETECT algorithm or the use of a combination of pulmonary function testing (forced vital capacity/diffusing capacity of the lung for carbon monoxide ratio) and N-terminal-pro-brain natriuretic peptide levels. Symptomatic patients, those with an elevated tricuspid regurgitation velocity on echocardiogram with or without secondary echocardiographic features of PAH, and those who screen positive on the DETECT or other pulmonary function test algorithms should undergo right heart catheterisation. Exercise echocardiography or cardiopulmonary exercise testing, nailfold capillaroscopy and molecular biomarkers are promising but, as yet, unproven potential options. Future screening studies should employ systematic catheterisation to define the true predictive values for PAH.

Screening can detect PAH at an early stage of the disease, which permits earlier medical interventions and may improve outcomes in systemic sclerosis patients.bit.ly/2Q5akGu

Biomarkers for Pulmonary Vascular Remodeling in Systemic Sclerosis: A Pathophysiological Approach

Pulmonary arterial hypertension (PAH) is a severe complication of systemic sclerosis (SSc) associated with high morbidity and mortality. There are several biomarkers of SSc-PAH, reflecting endothelial physiology, inflammation, immune activation, extracellular matrix, metabolic changes, or cardiac involvement. Biomarkers associated with diagnosis, disease severity and progression have been identified, however, very few have been tested in a prospective setting. Some antinuclear antibodies such as nucleosome antibodies (NUC), anti-centromere antibodies (CENP-A/B) and anti-U3-ribonucleoprotein (anti-U3-RNP) are associated with PAH while anti-U1-ribonucleoprotein (anti-U1-RNP) is associated with a reduced PAH risk. Anti-endothelin receptor and angiotensin-1 receptor antibodies might be good markers of SSc-PAH and progression of pulmonary vasculopathy. Regarding the markers reflecting immune activation and inflammation, there are many inconsistent results. CXCL-4 was associated with SSc progression including PAH and lung fibrosis. Growth differentiation factor (GDF)-15 was associated with PAH and mortality but is not specific for SSc. Among the metabolites, kynurenine was identified as diagnostic marker for PAH, however, its pathologic role in the disease is unclear. Endostatin, an angiostatic factor, was associated with heart failure and poor prognosis. Established heart related markers, such as N-terminal fragment of A-type natriuretic peptide/brain natriuretic peptide (NT-proANP, NT-proBNP) or troponin I/T are elevated in SSc-PAH but are not specific for the right ventricle and may be increased to the same extent in left heart disease. Taken together, there is no universal specific biomarker for SSc-PAH, however, there is a pattern of markers that is strongly associated with a risk of vascular complications in SSc patients. Further comprehensive, multicenter and prospective studies are warranted to develop reliable algorithms for detection and prognosis of SSc-PAH.

Pros and Cons of Echocardiography in the Screening, Diagnosis and Follow-up of Patients with Systemic Sclerosis Pulmonary Arterial Hypertension – a Rheumatologist's Perspective

Purpose

Our objective was to review the evidence regarding echocardiography in patients with systemic sclerosis (SSc) and possible pulmonary hypertension (PH).

Methods

The literature was reviewed. In addition, a survey was conducted of 315 rheumatologists/internists with a self-declared interest in SSc, to determine their preferred use of echocardiograms.

Results

The most relevant literature findings come from two studies, the DETECT study and one from the Australian Scleroderma Interest Group. In both these studies, it appears that the use of non-echocardiographic variables such as pulmonary function tests (PFTs) and values of serum N-terminal pro-brain natriuretic peptide (NT-proBNP), are adequate on their own in suggesting which patients are at high risk of PH. Echocardiograms added very little information and in fact may confuse the picture by appearing to be normal when in fact underlying PH is present. With regard to the survey, 157 physicians (49.8%) responded. Of those, 67% felt that an echocardiogram should be ordered on every patient with SSc every year. Ninety-five percent (95%) said the reason was to screen for the development of significant PH, 65% said the reason was to screen for the development of significant intrinsic cardiac disease and 38% said that the reason was to adhere to accepted international recommendations.

Conclusions

Despite popular belief and current recommendations, in the opinion of the author, echocardiograms are not necessary in every SSc patient every year. Cheaper tests such as PFTs and NT-proBNP are adequate in most cases to suggest when a right heart catheterization should be performed.

Connective tissue disease-related pulmonary arterial hypertension

Over the past two decades, there have been several advances in the assessment and management of connective tissue disease-related pulmonary arterial hypertension (CTD-PAH) that improved outcomes of the treatment of this lethal disease, and this will be the focus of this study. Systemic sclerosis is the leading cause of CTD-PAH, followed by systemic lupus erythematosus, mixed connective tissue disease, idiopathic inflammatory myositis, rheumatoid arthritis, and Sjogren's syndrome. Clinical registries have been invaluable in informing about the burden of disease, risk and prognostic factors, and temporal trends with respect to treatment and outcome in CTD-PAH. The major advances have centered on improved disease classification and diagnostic criteria, screening and early diagnosis, the emergence of evidence-based therapies including combination goal-orientated treatment strategies, and the establishment of centers with expertise in PAH.

Pulmonary Arterial Hypertension in Systemic Lupus Erythematosus: Prevalence and Predictors

OBJECTIVE

Pulmonary arterial hypertension (PAH) prevalence has been reported to be between 0.5% and 17% in systemic lupus erythematosus (SLE). This study assessed PAH prevalence and predictors in an SLE cohort.

METHODS

The Borg dyspnea scale, DLCO, N-terminal pro-brain natriuretic peptide (NT-proBNP), and Doppler echocardiographic (DE) were performed. An echocardiographic Doppler exercise test was conducted in selected patients. When DE systolic pulmonary arterial pressure was ≥ 45 mmHg or increased during exercise > 20 mmHg, a right heart catheterization was performed. Hemodynamic during exercise was measured if rest mean pulmonary arterial pressure was < 25 mmHg.

RESULTS

Of the 203 patients with SLE, 152 were included. The mean age was 44.9 ± 12.3 years, and 94% were women. Three patients had known PAH. The algorithm diagnosed 1 patient with chronic thromboembolic pulmonary hypertension and 5 with exercise-induced pulmonary artery pressure increase (4 with occult left diastolic dysfunction). These patients had significantly more dyspnea, higher NT-proBNP, and lower DLCO.

CONCLUSION

These data confirm the low prevalence of PAH in SLE. In our cohort, occult left ventricular diastolic dysfunction was a frequent diagnosis of unexplained dyspnea. Dyspnea, DLCO, and NT-proBNP could be predictors of pulmonary hypertension in patients with SLE.

No changes in N-terminal pro-brain natriuretic peptide in a longitudinal cohort of patients with systemic sclerosis-associated pulmonary arterial hypertension on therapy with bosentan

AIM

The aim of this study was to evaluate N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with systemic sclerosis (SSc)-associated pulmonary arterial hypertension (PAH) and changes after therapy with bosentan.

METHOD

Twenty-one patients with SSc-PAH on bosentan therapy were enrolled. PAH was diagnosed by right heart catheterization. NT-proBNP levels, 6-min walking test (6MWT), Doppler echocardiography to estimated systolic pulmonary arterial pressure (sPAP), New York Heart Association (NYHA) functional class for dyspnea and carbon monoxide lung diffusion capacity (DLco) were recorded at baseline, and after 1 and 2 years. Fifty-two SSc patients without PAH were also evaluated as controls.

RESULTS

NT-proBNP plasma levels were significantly higher in SSc-PAH at 385 pg/mL (SD ± 427) than in SSc without PAH and 72 pg/mL (SD ± 52, P < 0.001) at baseline, but did not significantly change following bosentan therapy at 1 year (330 pg/mL [SD ± 291] and 2 years (374 pg/mL [SD ± 291]). However, NYHA class significantly improved at 2 years (P = 0.01) as well as 6MWT (P = 0.04). NT-proBNP levels were positively correlated only with sPAP but not with DLco, NYHA class or 6MWT.

CONCLUSIONS

NT-proBNP levels were found to be significantly higher in SSc-PAH at baseline. Serial assessment of NT-proBNP in SSc-PAH patients on bosentan therapy showed no relation to the clinical improvement. This suggests that NT-proBNP may lack 'sensitivity to change', but further studies are warranted to assess the role of NT-proBNP as a biomarker of the therapeutic response in larger cohorts of SSc patients.

The inclusion of N-terminal pro-brain natriuretic peptide in a sensitive screening strategy for systemic sclerosis-related pulmonary arterial hypertension: a cohort study

INTRODUCTION

Pulmonary arterial hypertension (PAH) is a major cause of mortality in systemic sclerosis (SSc). Screening guidelines for PAH recommend multiple investigations, including annual echocardiography, which together have low specificity and may not be cost-effective. We sought to evaluate the predictive accuracy of serum N-terminal pro-brain natriuretic peptide (NT-proBNP) in combination with pulmonary function tests (PFT) (‘proposed’ algorithm) in a screening algorithm for SSc-PAH.

METHODS

We evaluated our proposed algorithm (PFT with NT-proBNP) on 49 consecutive SSc patients with suspected pulmonary hypertension undergoing right heart catherisation (RHC). The predictive accuracy of the proposed algorithm was compared with existing screening recommendations, and is presented as sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV).

RESULTS

Overall, 27 patients were found to have pulmonary hypertension (PH) at RHC, while 22 had no PH. The sensitivity, specificity, PPV and NPV of the proposed algorithm for PAH was 94.1%, 54.5%, 61.5% and 92.3%, respectively; current European Society of Cardiology (ESC)/European Respiratory Society (ERS) guidelines achieved a sensitivity, specificity, PPV and NPV of 94.1%, 31.8%, 51.6% and 87.5%, respectively. In an alternate case scenario analysis, estimating a PAH prevalence of 10%, the proposed algorithm achieved a sensitivity, specificity, PPV and NPV for PAH of 94.1%, 54.5%, 18.7% and 98.8%, respectively.

CONCLUSIONS

The combination of NT-proBNP with PFT is a sensitive, yet simple and non-invasive, screening strategy for SSc-PAH. Patients with a positive screening result can be referred for echocardiography, and further confirmatory testing for PAH. In this way, it may be possible to shift the burden of routine screening away from echocardiography. The findings of this study should be confirmed in larger studies.

Saudi Guidelines on the Diagnosis and Treatment of Pulmonary Hypertension: Biomarkers in pulmonary arterial hypertension

The biomarker is an indicaror of a biological or pathological process.

Clinical observations, measures or environmental events, or measured laboratory values can all be biomarkers in the appropriate setting. An ideal biomarker reflects the underlying biological process, predicts clinical events, is easily obtainable, is reproducible and is not prohibitively expensive. This typically requires validation in longitudinal cohort studies. Biomarkers may help understand the pathological mechanisms responsible for the disease, help as screening tools, predict disease worsening or decline, and determine adequacy of response to therapeutic interventions.

Screening and diagnostic modalities for connective tissue disease-associated pulmonary arterial hypertension: a systematic review

OBJECTIVE

Pulmonary arterial hypertension (PAH) is a frequent complication in connective tissue diseases (CTD), especially in systemic sclerosis (SSc), and is associated with a high degree of morbidity and mortality. We undertook a systematic review for the screening tests for CTD-PAH.

METHODS

A systematic literature search of PAH in CTD was performed in available databases through June 2012. Our evaluation of diagnostic tests was focused on patients with PAH confirmed by right heart catheterization (RHC).

RESULTS

The search resulted in 2805 titles and 838 abstracts. Our final inclusion encompassed 22 articles-six of which were case-control studies and 16 were cohort studies. Twelve studies assessed the tricuspid regurgitation velocity (VTR) or equivalent right ventricular systolic pressure (RVSP) using transthoracic echocardiogram (TTE) as a threshold for RHC in patients suspected as having PAH. The screening threshold for RHC was VTR from >2.73 to >3.16 m/s without symptoms or 2.5-3.0m/s with symptoms and resulted in 20-67% of patients having RHC-proven PAH. Three studies looked at pulmonary function tests and found that a low lung diffusing capacity for carbon monoxide (DLCO) (45-70% of predicted) is associated with a 5.6-7.4% development of PAH, and a decline in DLCO% is associated with an increase in the specificity (for DLCO ≤ 60%, spec = 45%; and for DLCO ≤ 50%, spec = 90%) for PAH. Five studies assessed N-terminal prohormone of brain natriuretic peptide (NT-ProBNP), where a cutoff >239 pg/ml had a sensitivity of 90-100%.

CONCLUSIONS

Our systematic review revealed that most evidence exists for TTE, pulmonary function tests, and NT-ProBNP for screening and diagnosis of SSc-PAH; however, more robust studies are needed.

Non-invasive evaluation of hemodynamics in pulmonary hypertension by a Septal angle measured by computed tomography pulmonary angiography: Comparison with right-heart catheterization and association with N-terminal pro-B-type natriuretic peptide

The septal angle, an angle between the interventricular septum and the line connecting the sternum midpoint and thoracic vertebral spinous process, as measured by computed tomographic pulmonary angiography (CTPA), has been observed to be increased in patients with pulmonary hypertension (PH), but its meaning remains unclear. The aim of this study was to investigate the potential role of the septal angle in evaluating hemodynamics and its association with N-terminal pro-B-type natriuretic peptide (NT-proBNP) in patients with PH. Patients with PH (n=106), including 76 with chronic thromboembolic pulmonary hypertension (CTEPH) and 30 with pulmonary artery hypertension (PAH), were retrospectively reviewed. The patients underwent CTPA prior to right-heart catheterization. The septal angle was measured on transversal CTPA images. Hemodynamic parameters were evaluated by right-heart catheterization. The level of plasma NT-proBNP was measured by enzyme-linked sandwich immunoassay. The septal angle had a moderate correlation with cardiac output (CO; r=−0.535, P=0.000) and a high correlation with pulmonary vascular resistance (PVR; r=0.642, P=0.000). The mean level of NT-proBNP in PH was 1,716.09±1,498.30 pg/ml, which correlated with the septal angle (r=0.693, P=0.000). In a stepwise forward regression analysis, the Septal angle was entered into the final equation for predicting PVR, leading to the following equation: PVR = 28.256 × Septal angle - 728.72. In CTEPH, the Septal angle strongly correlated with NT-proBNP (r=0.668, P=0.000) and PVR (r=0.676, P=0.000). In PAH, the Septal angle strongly correlated with NT-proBNP (r=0.616, P=0.003) and PVR (r=0.623, P=0.000). The CTPA-derived Septal angle is a superior predictor for evaluating and monitoring the level of NT-proBNP and PVR in patients with PH.

Serum endothelin-1 and NT-proBNP, but not ADMA, endoglin and TIMP-1 levels, reflect impaired right ventricular function in patients with systemic sclerosis

Background

Heart and pulmonary involvement is a leading cause of systemic sclerosis (SSc)-related deaths.

Objectives

The aim of our study was to assess if biochemical markers of right ventricular (RV) overload, endothelial function and collagen metabolism can predict RV dysfunction assessed by Doppler echocardiography in SSc patients.

Methods

We prospectively studied 111 consecutive patients (101 F, 10 M, age 54.2 ± 13.8 years) with diagnosed SSc (mean disease duration 9.4 ± 11.4 years) and a group of 21 age-matched subjects (18 F, 3 M, age 49.3 + 10.5 years). We performed transthoracic echocardiography (Phillips iE 33) and measured serum endothelin-1 (ET-1), N-terminal pro-brain natriuretic peptide (NT-proBNP), asymmetric dimethylarginine (ADMA), endoglin and human tissue inhibitor of matrix metalloproteinase (TIMP-1) concentration.

Results

Median serum NT-proBNP level in SSc patients was 133.5 (range 21.86–17,670 pg/ml) and was significantly higher than in controls (p = 0.0002). Moreover, the median serum ET-1 level of 1.49 (range 0.26–8.75 pg/ml) was higher in SSc patients (p = 0.002). However, no significant differences in ADMA, TIMP-1 and endoglin serum concentration between SSc patients and controls were observed. Serum NT-proBNP concentration correlated positively with echocardiographic signs of RV overload: tricuspid regurgitation pressure gradient (r = 0.38, p = 0.0004) and RV Tei index (r = 0.25, p = 0.01). ET-1 serum level correlated negatively with tricuspid annular plane systolic excursion (r = −0.4, p = 0.01) and positively with inferior vena cava diameter measured at expiration (r = 0.38, p = 0.0002). The echocardiographic signs of RV overload were significantly more pronounced in the highest NT-proBNP tertile (>195 pg/ml) group than in the lowest one (<88 pg/ml).

Conclusions

Serum ET-1 and NT-proBNP, but not endoglin, ADMA and TIMP-1 levels correlating with the echocardiographic parameters of RV overload, can be considered as noninvasive indicators of RV dysfunction in SSc patients.

N-terminal pro-brain natriuretic peptide in a novel screening algorithm for pulmonary arterial hypertension in systemic sclerosis: a case-control study

Introduction

Pulmonary arterial hypertension is a major cause of mortality in systemic sclerosis. N-terminal pro-brain natriuretic peptide (NT-proBNP) has emerged as a candidate biomarker that may enable the early detection of systemic sclerosis-related pulmonary arterial hypertension (SSc-PAH). The objective of our study was to incorporate NT-proBNP into a screening algorithm for SSc-PAH that could potentially replace transthoracic echocardiography (TTE) as a more convenient and less costly "first tier" test.

Methods

NT-proBNP levels were measured in patients from four clinical groups: a group with right heart catheter (RHC)-diagnosed SSc-PAH before commencement of therapy for PAH; a group at high risk of SSc-PAH based on TTE; a group with interstitial lung disease; and systemic sclerosis (SSc) controls with no cardiopulmonary complications. NT-proBNP levels were compared by using ANOVA and correlated with other clinical variables by using simple and multiple linear regression. ROC curve analyses were performed to determine the optimal cut point for NT-proBNP and other clinical variables in prediction of PAH.

Results

NT-proBNP was highest in the PAH group compared with other groups (P < 0.0001), and higher in the risk group compared with controls (P < 0.0001). NT-proBNP was positively correlated with systolic pulmonary artery pressure (PAP) on TTE (P < 0.0001), and mean PAP (P = 0.013), pulmonary vascular resistance (P = 0.005), and mean right atrial pressure (P = 0.006) on RHC. A composite model wherein patients screened positive if NT-proBNP was ≥ 209.8 pg/ml, and/or DLCO_corr was < 70.3% with FVC/DLCO_corr ≥ 1.82, had a sensitivity of 100% and specificity of 77.8% for SSc-PAH.

Conclusion

We have proposed a screening algorithm for SSc-PAH, incorporating NT-proBNP level and PFTs. This model has high sensitivity and specificity for SSc-PAH and, if positive, should lead to TTE and confirmatory testing for PAH. This screening algorithm must be validated prospectively.

B-type natriuretic peptide in rheumatic diseases: a cardiac biomarker or a sophisticated acute phase reactant?

Natriuretic peptides (NP) are secreted by cardiomyocytes and are reliable markers of cardiac dysfunction and cardiovascular risk by reflecting myocardial stress due to various etiologies. Clinical and occult heart involvement is frequently observed in patients with rheumatic diseases and is associated with increased morbidity and mortality. Cardiac disease in autoimmune disorders encompasses different pathophysiological mechanisms including inflammation and involving either the myocardium or the coronary/pulmonary vessels. Although the major trigger for the synthesis and release of NP is myocardial strain, there is also some support for the concept that inflammation stimulates the neurohormonal system of the heart leading to increased production of NP. Recent studies have focused on the association of NP and inflammation in the context of rheumatic diseases, suggesting that up-regulation of neurohormonal axis in these conditions is linked with inflammation. Additionally the NP have a well-documented role in the diagnostic work-up of patients with connective tissue disease who are at increased risk of developing pulmonary hypertension, as the right ventricular overload results in increased NP synthesis and release. However the precise role of NP in the assessment and the management of cardiovascular risk in patients with rheumatic diseases is yet to be established. In the current article we discuss the pathophysiologic mechanisms involved in enhanced NP expression in patients with rheumatic disorders and their potential clinical implication in daily practice.

Systemic sclerosis and the heart: current diagnosis and management

PURPOSE OF REVIEW

When present clinically, cardiac involvement in systemic sclerosis (SSc) is a major risk factor for death. It is therefore vitally important to understand the epidemiology, screening, diagnosis, and treatment of the cardiac manifestations of SSc.

RECENT FINDINGS

The epidemiology of cardiac involvement in SSc has been the subject of several recent studies. Most importantly, the prevalence of overt left ventricular (LV) systolic dysfunction and its associated risk factors have been defined, and patients with diffuse cutaneous SSc appear to be most susceptible to direct cardiac involvement. From a diagnostic and screening standpoint, tissue Doppler echocardiography and natriuretic peptides have provided fresh insight into subclinical cardiac dysfunction in SSc. Newer techniques, such as speckle-tracking echocardiography, diffuse myocardial fibrosis imaging, and absolute myocardial perfusion imaging, are poised to further advance our knowledge. Lastly, there is now consistent observational data to suggest a central role for calcium channel blockers in the treatment of microvascular ischemia and prevention of overt LV systolic dysfunction, although randomized controlled trials are lacking.

SUMMARY

Recent studies have improved our understanding of cardiac involvement in SSc. Nevertheless, key questions regarding screening, diagnosis, and treatment remain. Novel diagnostic techniques and multicenter studies should yield important new data, which will hopefully ultimately result in improved outcomes.

Usefulness of serial N-terminal pro-B-type natriuretic peptide measurements for determining prognosis in patients with pulmonary arterial hypertension

Previous studies have shown the prognostic benefit of N-terminal pro-brain natriuretic peptide (NT-pro-BNP) in pulmonary arterial hypertension (PAH) at time of diagnosis. However, there are only limited data on the clinical utility of serial measurements of the inactive peptide NT-pro-BNP in PAH. This study examined the value of serial NT-pro-BNP measurements in predicting prognosis PAH. We retrospectively analyzed all available NT-pro-BNP plasma samples in 198 patients who were diagnosed with World Health Organization group I PAH from January 2002 through January 2009. At time of diagnosis median NT-pro-BNP levels were significantly different between survivors (610 pg/ml, range 6 to 8,714) and nonsurvivors (2,609 pg/ml, range 28 to 9,828, p <0.001). In addition, NT-pro-BNP was significantly associated (p <0.001) with other parameters of disease severity (6-minute walking distance, functional class). Receiver operating curve analysis identified ≥1,256 pg/ml as the optimal NT-pro-BNP cutoff for predicting mortality at time of diagnosis. Serial measurements allowed calculation of baseline NT-pro-BNP (i.e., intercept obtained by back-extrapolation of concentration-time graph), providing a better discrimination between survivors and nonsurvivors than NT-pro-BNP at time of diagnosis alone (p = 0.010). Furthermore, a decrease of NT-pro-BNP of >15%/year was associated with survival. In conclusion, a serum NT-pro-BNP level ≥1,256 pg/ml at time of diagnosis identifies poor outcome in patients with PAH. In addition, a decrease in NT-pro-BNP of >15%/year is associated with survival in PAH.

Early detection of pulmonary vascular disease in pulmonary arterial hypertension: time to move forward

Pulmonary arterial hypertension (PAH) can be a rapidly progressive disorder and is associated with high rate of mortality, despite medical intervention. With the availability of effective therapy, early disease detection is an important strategic objective to improve treatment outcomes. Resting echocardiography is currently the recommended screening modality for high-risk population groups. However, it is clear that derangements in resting haemodynamics (and symptoms) are late sequelae of the pathobiological processes that begin in the distal pulmonary arteries. Exercise stress may unmask early pulmonary vascular dysfunction but the definition, clinical significance, and natural history of 'exercise PAH' remain undefined. We will review the currently available and potential future strategies aimed at early disease detection, and propose that ultimately the way forward is to detect disease at a stage prior to the rise in resting pulmonary artery pressure.

Pulmonary hypertension in systemic sclerosis

OBJECTIVES

To discuss the clinical subtypes, pathogenesis, pathology, diagnostic evaluation, treatment options, and prognosis of pulmonary hypertension in systemic sclerosis (SSc-PH) and highlight its fundamental differences from idiopathic pulmonary arterial hypertension (IPAH).

METHODS

A Medline search for articles published between January 1969 and June 2010 was conducted using the following keywords: scleroderma, systemic sclerosis, pulmonary hypertension, pulmonary arterial hypertension, pulmonary veno-occlusive disease, pathogenesis, pathology, investigation, treatment, and prognosis. The essential differences from IPAH in pathogenesis and histopathologic findings were highlighted and the limitations of some of the investigations used were emphasized. The differences in response to currently accepted therapy and prognosis were also reviewed.

RESULTS

In scleroderma, pulmonary hypertension can be present in isolation or along with interstitial lung disease and left heart disease. In SSc-PH, the unique histopathologic findings in the lungs include intimal fibrosis, absence of plexiform lesions, and a high prevalence of pulmonary veno-occlusive disease-like lesions. Both "6-minute walk test" and NT-proBNP have their limitations in the evaluation of SSc-PH. For treatment, calcium channel blockers are ineffective and anticoagulation should be used with caution. Currently approved therapies are not as effective and prognosis is much worse in SSc-PH compared with IPAH.

CONCLUSIONS

SSc-PH is a complex condition with poorer response to therapy and worse outcome compared with that of IPAH. Recent findings have shed some light about the pathophysiology and pathogenesis of SSc-PH. Further research in this area is warranted to better understand the complex pathogenesis and devise better therapeutic strategies.

Comparison of brain natriuretic peptide (BNP) and NT-proBNP in screening for pulmonary arterial hypertension in patients with systemic sclerosis

OBJECTIVE

To compare the performance of brain natriuretic peptide (BNP) and N-terminal pro-brain natriuretic peptide (NT-proBNP) in screening for pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc).

METHODS

Between January 2008 and March 2009, outpatients referred to our unit and satisfying LeRoy criteria for SSc were assessed for PAH. Doppler echocardiography, BNP measurement, and NT-proBNP measurement were done concomitantly for a complete clinical, instrumental, and biochemical evaluation. Right-heart catheterization was carried out in cases of suspected PAH [estimated pulmonary arterial pressure (PAP) ≥ 36 mm Hg; diffusion capacity for carbon monoxide (DLCO) ≤ 50% of predicted value; 1-year DLCO decline ≥ 20% in absence of pulmonary fibrosis; unexplained dyspnea].

RESULTS

One hundred thirty-five patients were enrolled (124 women, 11 men; 96 limited SSc, 39 diffuse SSc); precapillary PAH was found in 20 patients (15 limited SSc, 5 diffuse SSc). The estimated PAP correlated with both BNP (R = 0.3; 95% CI 0.14-0.44) and NT-proBNP (R = 0.3, 95% CI 0.14-0.45). BNP [area under the curve (AUC) 0.74, 95% CI 0.59-0.89] was slightly superior to NT-proBNP (AUC 0.63, 95% CI 0.46-0.80) in identification of PAH, with diagnosis cutoff values of 64 pg/ml (sensitivity 60%, specificity 87%) and 239.4 pg/ml (sensitivity 45%, specificity 90%), respectively. BNP (log-transformed, p = 0.032) and creatinine (p = 0.049) were independent predictors of PAH, while NT-proBNP was not (p = 0.50).

CONCLUSION

In our single-center study, the performance of BNP was slightly superior to that of NT-proBNP in PAH screening of patients with SSc, although normal levels of these markers do not exclude diagnosis. We observed that impaired renal function is associated with an increased risk of PAH in SSc. Further multicenter studies are needed to confirm our results (ClinicalTrials.gov ID NCT00617487).

Left atrial volume and N-terminal pro-B type natriuretic peptide are associated with elevated pulmonary artery pressure in patients with systemic sclerosis

Early detection of pulmonary hypertension (PH) in patients with systemic sclerosis (SSc) is essential as it leads to substantial morbidity and mortality irrespective of its etiology. The aim of our study was to determine whether noninvasive biochemical and/or echocardiographic indices can predict the presence of PH in these patients. We prospectively studied 66 patients (mean age of 57.7 +/- 12.1 years, 63 women) with SSc without clinical manifestations of heart failure. All patients underwent standard and tissue Doppler echocardiography. Plasma N-terminal pro-B type natriuretic peptide (NT-proBNP) and asymmetric dimethylarginine (ADMA) levels were also measured. In 24 (36%) patients, the diagnosis of PH was established by echocardiography (systolic pulmonary artery pressure value > or =40 mmHg). Left atrial (LA) volume, NT-proBNP, ADMA, ratio of early transmitral filling velocity to early diastolic velocity of the mitral annulus (mitral E/E (m)), and right ventricular myocardial performance index (MPI) were univariate predictors of PH. In multivariate analysis, NT-proBNP, LA volume, and right ventricular MPI were independent predictors of PH in SSc patients. LA volume and NT-proBNP may be useful noninvasive markers for the prediction of elevated pulmonary artery pressure in patients with SSc. These parameters should be considered when assessing this population for risk stratification and for identification of patients demanding further investigation and institution of specific therapy for the disease at the time when it is most likely to be effective.

NT-proBNP levels in systemic sclerosis: association with clinical and laboratory abnormalities

OBJECTIVE

To identify factors related to NT-proBNP levels in systemic sclerosis (SSc).

DESIGN AND METHODS

NT-proBNP was measured in 119 patients with SSc and 20 controls. Patients with transtricuspid gradient (TG) > or =36 mm Hg or > or =31 mmHg plus dyspnea were considered to have suspected systemic sclerosis-associated pulmonary arterial hypertension (SScPAH).

RESULTS

Increasing age, NYHA functional class, skin score, history of systemic arterial hypertension (SAH), anticentromere antibodies, diastolic dysfunction, reduced pulmonary diffusing capacity, and TG were positively associated with NT-proBNP. In multivariable linear regression, TG, age, and SAH were independently associated to NT-proBNP levels. An ROC curve analysis (with an area under the curve of 0.89, 95% CI: 0.83-0.95) suggested a cutoff of 157.8pg/mL to identify patients with suspected SScPAH, presenting a sensitivity of 100% (78.1-100) and specificity of 72.3% (62.3-80.5).

CONCLUSIONS

NT-proBNP levels are related to clinical and laboratory abnormalities in SSc. The results indicate that NT-proBNP may be a useful tool in the evaluation of SScPAH.

Early Detection of Cardiac Involvement in Systemic Sclerosis Assessed by Tissue-Doppler Echocardiography: Relationship with Neurohormonal Activation and Endothelial Dysfunction

Objective.

Cardiopulmonary complications are common in patients with systemic sclerosis (SSc). We assessed cardiac involvement in patients with SSc using echocardiography and investigated the association of N-terminal pro-brain natriuretic peptide (NT-proBNP) and asymmetric dimethylarginine (ADMA) with echocardiographic measures of myocardial function in sera of patients with SSc who had no symptoms of heart failure.

Methods.

We prospectively studied 52 patients with SSc (mean age 55.7 ± 10.1 yrs, 51 women), with conventional and tissue-Doppler echocardiography. Plasma NT-proBNP and ADMA levels were measured in all patients. Data were compared with those obtained from 25 healthy controls comparable for age and sex.

Results.

Patients with SSc had impaired left ventricular (LV) and right ventricular diastolic function expressed by inverted ratio of peak early to peak late transmitral (Mit E/A) and transtricuspid velocity and increased left atrial diameter compared with controls. Peak systolic mitral lateral annular motion velocity and peak early diastolic mitral lateral annular motion velocity (LV Em) were lower, while LV E/Em ratio was higher, in patients with SSc compared to controls. ADMA was significantly related with LV Em and E/Em ratio. NT-proBNP was associated with Mit E, Mit E/A ratio and mitral deceleration time. Significant correlation was also observed between NT-proBNP and ADMA levels.

Conclusion.

Depressed cardiac function is common, even in asymptomatic patients with SSc. NT-proBNP and ADMA are significantly correlated with echocardiographic abnormalities, providing a potent link for cardiac function, neuroendocrine derangement, and endothelial dysfunction in patients with SSc who have cardiac disease.

Brain natriuretic peptide in pulmonary arterial hypertension: biomarker and potential therapeutic agent

B-type natriuretic peptide (BNP) is a member of the natriuretic peptide family, a group of widely distributed, but evolutionarily conserved, polypeptide mediators that exert myriad cardiovascular effects. BNP is a potent vasodilator with mitogenic, hypertrophic and pro-inflammatory properties that is upregulated in pulmonary hypertensive diseases. Circulating levels of BNP correlate with mean pulmonary arterial pressure (mPAP) and pulmonary vascular resistance (PVR) in patients with pulmonary arterial hypertension (PAH). Elevated plasma BNP levels are associated with increased mortality in patients with PAH and a fall in BNP levels after therapy is associated with improved survival. These findings have important clinical implications in that a noninvasive blood test may be used to identify PAH patients at high-risk of decompensation and to guide pulmonary vasodilator therapy. BNP also has several biologic effects that could be beneficial to patients with PAH. However, lack of a convenient method for achieving sustained increases in circulating BNP levels has impeded the development of BNP as a therapy for treating pulmonary hypertension. New technologies that allow transdermal or oral administration of the natriuretic peptides have the potential to greatly accelerate research into therapeutic use of BNP for cor pulmonale and pulmonary vascular diseases. This review will examine the basic science and clinical research that has led to our understanding of the role of BNP in cardiovascular physiology, its use as a biomarker of right ventricular function and its therapeutic potential for managing patients with pulmonary vascular disease.

The complexity of managing systemic sclerosis: screening and diagnosis

The difficulties inherent in diagnosing, screening and treating SSc are reflected by the complex pathology of the disease, which involves the development of severe organ-based complications that reduce both quality of life and overall survival. Early detection and prompt treatment of such complications depend upon a successful and timely screening strategy, which, in turn, requires cooperation between disciplines and good collaborative links at all stages of the disease. Establishment of a disease registry for SSc may also be of benefit, as such registries facilitate longitudinal observation of trends in disease presentation, management and outcome. They may also help to determine potential risk factors and identify those patient subgroups that face the highest risk of developing disease. In patients with known or suspected SSc, a panel of disease-specific markers--such as autoantibodies, cell activation markers and markers of organ involvement--may help to establish the diagnosis and assess prognosis; however, changes in serum levels of such markers throughout the course of SSc should be interpreted with caution, as they may not always correlate with disease activity. Nail-fold capillaroscopy is a promising tool for SSc assessment and may provide useful diagnostic and prognostic information, although further research is required to clarify its role in evaluating disease evolution.

Pulmonary arterial hypertension: the most devastating vascular complication of systemic sclerosis

Pulmonary arterial hypertension (PAH) is a devastating vascular complication of a number of CTDs. In patients with SSc, PAH has a dramatic impact on prognosis and survival and is the single most common cause of disease-related death.Yearly echocardiographic screening for PAH is recommended in patients with SSc. If suspected, confirmation of PAH diagnosis by right heart catheterization is necessary. Treatment goals for patients with PAH associated with SSc (PAH-SSc) aim to slow disease progression and improve quality of life. Some measures used to gauge the effect of treatment in patients with PAH-SSc remain to be fully validated; the 6-min walk distance, for example, is a simple and reproducible means of assessing exercise capacity, but there exists a need to understand what constitutes a clinically relevant change in this specific patient population. Currently, pharmacological intervention in PAH-SSc may target one or more of three pathophysiological pathways in PAH. The prostacyclin analogue epoprostenol has been shown to improve exercise capacity and haemodynamics in PAH-SSc patients and similar data are available from smaller studies on trepostinil and iloprost. The dual endothelin receptor antagonist bosentan has been shown to improve exercise capacity and haemodynamics in PAH-SSc, and similar data have been obtained in small numbers of patients treated with the endothelin receptor A antagonists sitaxsentan and ambrisentan. Impaired production of nitric oxide may be addressed by inhibiting phosphodiesterase type-5 with sildenafil or possibly tadalafil. Combinations of multiple targeted therapies may be beneficial to this patient population.

Asymmetrical dimethylarginine in systemic sclerosis-related pulmonary arterial hypertension

OBJECTIVES

SSc is a CTD characterized by vascular involvement, with generalized disturbance of the microcirculation, which may lead to pulmonary artery hypertension (PAH). Asymmetrical dimethylarginine (ADMA) is an endogenous nitric oxide (NO) inhibitor. Increased concentrations of plasma ADMA may also contribute to endothelial dysfunction in patients with pulmonary vascular disease. The aim of our study was to elucidate the possible relationship between serum ADMA and PAH in patients with SSc. Moreover, we sought to investigate the effect of ADMA levels on the functional capacity of these patients.

METHODS

Plasma ADMA levels were measured in 66 patients with SSc (63 females, mean age 57.8 +/- 12.8 yrs, median duration of disease 9.9 yrs, 47 with lcSSc and 19 with dcSSc disease) and 30 healthy controls (29 females, mean age 58.2 +/- 8.4 yrs). Systolic pulmonary artery pressure (sPAP) assessed by echocardiography, lung function tests, 6-min walk test (6MWT) and serum ADMA levels were recorded from patients.

RESULTS

In 24 patients, the diagnosis of PAH was established. Mean value of ADMA for SScPAH patients was 0.44 +/- 0.22 micromol/l compared with 0.26 +/- 0.18 micromol/l for patients without PAH and 0.25 +/- 0.20 micromol/l for controls (P = 0.001). ADMA levels were inversely correlated with the 6MWT (r = -0.55, P = 0.005).

CONCLUSIONS

In patients with SScPAH, increased ADMA serum levels and their negative association with exercise capacity suggests that the NO pathway is involved in the development of pulmonary vascular disease.

High N-terminal pro-brain natriuretic peptide levels and low diffusing capacity for carbon monoxide as independent predictors of the occurrence of precapillary pulmonary arterial hypertension in patients with systemic sclerosis

OBJECTIVE

To evaluate predictors of pulmonary arterial hypertension (PAH) in a prospective cohort of patients with systemic sclerosis (SSc).

METHODS

Routine clinical assessments as well as measurements of the diffusing capacity for carbon monoxide/alveolar volume (DLCO/VA) ratio and N-terminal pro-brain natriuretic peptide (NT-proBNP) level were performed in a prospective cohort of 101 SSc patients who did not have PAH or severe comorbidities. After a planned 36-month followup, we evaluated the predictive value of these parameters for the development of precapillary PAH, as demonstrated by cardiac catheterization, disease progression, and death. Criteria for cardiac catheterization were a systolic pulmonary artery pressure (PAP) of >40 mm Hg on echocardiography, a DLCO value of <50% without pulmonary fibrosis, and unexplained dyspnea.

RESULTS

Eight patients developed PAH, 29 had disease progression, and 10 died during a median followup of 29 months. Kaplan-Meier analysis identified the following baseline parameters as being predictors of PAH: DLCO/VA ratio <70% or <60% (P<0.01 for each comparison), elevated plasma NT-proBNP level (>97th percentile of normal; P = 0.005), echocardiographically estimated systolic PAP >40 mm Hg (P=0.08), and erythrocyte sedimentation rate >28 mm/hour (P=0.015). In multivariate analyses, an elevated baseline NT-proBNP level (hazard ratio [HR] 9.97 [95% confidence interval (95% CI) 1.69-62.42]) and a DLCO/VA ratio <60% (HR 36.66 [95% CI 3.45-387.6]) were predictors of the occurrence of PAH during followup. An increased NT-proBNP level together with a decreased DLCO/VA ratio of <70% was highly predictive of the occurrence of PAH during followup (HR 47.20 [95% CI 4.90-450.33]).

CONCLUSION

This prospective study identified a decreased DLCO/VA ratio and an increased NT-proBNP as predictors of PAH in SSc. Use of these markers should result in improved PAH risk stratification and allow earlier initiation of therapy.

Biological serum markers in the management of pediatric pulmonary arterial hypertension

Appropriate parameters are needed for the monitoring of children with pulmonary arterial hypertension (PAH). Various biologic markers seem to be of use in adults with PAH. No data are available on their value in children with PAH. In this study, the relation between serum markers, functional parameters, and hemodynamic variables in pediatric PAH and their ability to predict survival is determined. Serum N-terminal pro brain natriuretic peptide (NT-proBNP), uric acid, norepinephrine, and epinephrine were measured and correlated with invasive hemodynamics, functional parameters, and outcome in 29 pediatric patients with PAH who visited a tertiary reference center for pediatric PAH between 1997 and 2005. NT-proBNP correlated with functional class (R = 0.36; p = 0.03) and 6-min walking distance (6MWD) (R = -0.53; p < 0.001). Uric acid correlated with mean pulmonary arterial pressure, pulmonary vascular resistance, and cardiac index (R = 0.63, p = 0.01; R = 0.71, p = 0.03, and R = -0.65, p = 0.007, respectively). After initiation of treatment, NT-proBNP decreased. This decrease correlated with an increased 6MWD. Finally, norepinephrine and NT-proBNP levels were highly predictive for mortality. In this series of children with PAH, biologic markers were correlated with hemodynamics and functional capacity, as parameters of disease severity. The data indicate that these markers can be used to monitor treatment effects and predict mortality in pediatric PAH.

Non-invasive diagnostic and functional evaluation of cardiac involvement in patients with systemic sclerosis

Elevated serum brain natriuretic peptide (BNP) released from myocytes of ventricles upon stretch have been found in patients with isolated right ventricular (RV) pressure overload. However, limited data suggest that serum BNP may be elevated in systemic sclerosis (SSc) patients, especially with RV dysfunction. We assessed serum N-terminal proBNP (NT-proBNP) in SSc and evaluated whether it reflects the severity of RV overload. We prospectively studied 51 consecutive patients (47F, mean age 53.3 +/- 15.2 years) with SSc (mean disease duration 9 +/- 12.4 years). The control group formed 31 healthy subjects (27F, mean age 52.6 +/- 12.1 years). NT-proBNP level, 6-minute walking test (6MWT), and transthoracic echocardiography (TTE) for the assessment of RV overload were performed. Serum NT-proBNP exceeded the reference value of 125 pg/mL in 31 (61%) SSc patients. The mean serum log NT-proBNP concentration in SSc was higher than in controls (2.138 +/- 0.527 vs. 1.634 +/- 0.420 pg/mL, p < 0.001). 13 (25%) SSc patients have tricuspid regurgitation peak gradient (TRPG) exceeding 31 mmHg reflecting pulmonary arterial hypertension (PAH). The SSc presented other echocardiographic signs of RV overload. Mean 6MWT distance was shorter in SSc than in controls (528 +/- 100 vs. 617 +/- 80 m, p < 0.001). NT-proBNP level correlated positively with TRPG, RV diameter, RV Tei index and negatively with 6MWT distance. ROC analysis identified >115 pg/ml as the best NT-proBNP threshold predicting PAH for SSc patients (sensitivity 92%, specificity 44%). Results of our study suggest that NT-proBNP measurement is a useful screening method for PAH in SSc patients. Since elevated plasma NT-proBNP level reflects the degree of right ventricular overload and limitation of exercise capacity, abnormal NT-proBNP levels should imply further evaluation including echocardiography.

The clinical significance of serum N-terminal pro-brain natriuretic peptide in systemic sclerosis patients

We evaluated the clinical significance of serum N-terminal pro-brain natriuretic peptide (NT-proBNP) level in systemic sclerosis (SSc). We studied 45 SSc patients (30 with limited and 15 with diffuse cutaneous SSc) of mean age +/- SD 47.1 +/- 12.9 years, mean duration of disease 10.2 +/- 6.0 years, and 45 age- and sex-matched healthy controls. Pulmonary artery pressure was measured by echocardiography. Lung involvement was evaluated by pulmonary function testing and by using high-resolution computed tomography scores. Serum NT-proBNP levels were measured using a sandwich electrochemiluminescent immunoassay. Serum NT-proBNP levels were significantly higher in patients with SSc compared to healthy controls. When the patients were divided into clinical subsets, serum NT-proBNP was higher in diffuse SSc than in limited SSc. Serum NT-proBNP levels were found to be positively correlated with age, skin thickness score, and systolic pulmonary artery pressure and negatively correlated with percentage of carbon monoxide diffusion capacity (DLco). Multivariate analysis showed that serum NT-proBNP levels were positively correlated with age (p = 0.010), skin thickness score (p = 0.000), and blood pressure (p = 0.021) and negatively correlated with %DLco (p = 0.016). Fifty-seven percent of the variation in log (proBNP) can be explained by the multivariate model (R (2) = 0.57). Serum NT-proBNP levels were higher in SSc patients (particularly the diffuse subset) than in healthy controls and were found to be correlated with skin thickness and %DLco. We conclude that serum NT-proBNP may be a biologic marker of skin fibrosis and pulmonary vascular involvement in SSc.

NT-proBNP in chronic hypercapnic respiratory failure: A marker of disease severity, treatment effect and prognosis

BACKGROUND

Natriuretic peptides are considered as reliable indicators of left-heart failure (HF) and are useful for differential diagnosis of dyspnoea.

AIM

We evaluated the clinical significance of N-terminal pro-brain natriuretic peptide (NT-proBNP) in patients with chronic hypercapnic respiratory failure (CHRF).

METHODS

In 60 patients with CHRF, plasma concentrations of NT-proBNP were assessed at baseline and after treatment including non-invasive ventilation (NIV). The relationship of NT-proBNP to disease severity and its predictive value for survival were evaluated up to 4 years.

RESULTS

NT-proBNP levels were markedly elevated in patients with CHRF (n=60; geometric mean (SD) 546.4 (4.9) pg/mL; p<0.001) compared to healthy controls (n=182; 49.0 (2.2) pg/mL). After excluding patients with concomitant HF or renal impairment, levels were still increased (n=43; 393.2 (3.8) pg/mL; p<0.001). According to multivariate regression, hypoxia and exacerbation independently determined NT-proBNP levels (p<0.05 each). After initiation of NIV, blood gases and lung function improved and NT-proBNP decreased (-31.3 (0.3)%; p<0.001). During 22.5 (2.2) months follow-up, NT-proBNP was not significantly associated with survival in the total population, however, the subgroup of patients with levels >722 pg/mL (67th percentile) and no adherence to NIV displayed poor prognosis (hazard ratio=0.21; 95%-CI=0.022-0.580; p=0.0091).

CONCLUSIONS

NT-proBNP was highly elevated in patients with CHRF and correlated with the degree of respiratory impairment and exacerbation. Correspondingly, treatment including NIV led to reduction of NT-proBNP. These data indicate a potential role of NT-proBNP in assessing disease severity, treatment efficacy and prognosis in CHRF.

Therapy of pulmonary arterial hypertension in systemic sclerosis: An update

Pulmonary arterial hypertension (PAH) affects 10% to 15% of patients with systemic sclerosis and is a major cause for disease-related morbidity and mortality. Over the past decade, significant progress has been made in the understanding of the pathophysiologic mechanisms underlying PAH. This progress led to the development of several new treatment options and, as a result, dramatically improved survival among this severely affected cohort. The outcome in patients with scleroderma-related PAH is much worse than that in patients with idiopathic PAH, and unfortunately only a few studies have assessed treatment and outcome among patients suffering from connective tissue disease-related PAH. In recent years, publications of connective tissue disease subgroup analysis from large trials in PAH have emerged. We review the current treatment options for PAH and the evidence for their use in scleroderma-related PAH.

Surrogate end points in pulmonary arterial hypertension: assessing the response to therapy

Recent discoveries in the disease pathophysiology of pulmonary arterial hypertension have been translated into effective therapies tested in clinical trials. The studies have focused on surrogate and intermediate end points, thought to reflect quantity and quality of life, respectively. The authors present the necessary requirements for establishing the reliability and validity of such end points before they may be used dependably. The authors also review the available data, strengths, and weaknesses of potential end points in pulmonary arterial hypertension.